It is not seldom for the conventional bed mattresses to be discarded as a whole, rather than to be repaired, when the cushion member has lost the elasticity, which varies according to the materials used, the accessories such as side pads and upper/lower cover pads are wholly or partially damaged, soiled or discolored, and so on. That's because all parts of the mattresses, namely the cushion member and the accessories, are integrated into one single body, making it not easy to repair a part or parts of the mattress.